[PATCH net-next 20/30] net: dsa: mt7530: properly reset MT7531 switch

From: arinc9 . unal
Date: Mon May 22 2023 - 08:19:33 EST


From: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>

According to the document MT7531 Reference Manual for Development Board
v1.0, the SW_PHY_RST bit on the SYS_CTRL register doesn't exist for
MT7531. This is likely why forcing link-down on the MACs is necessary for
MT7531.

Therefore, do not set SW_PHY_RST on mt7531_setup().

Tested-by: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>
Signed-off-by: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>
---
drivers/net/dsa/mt7530.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 0c261ef87bee..aafb7415e2ce 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -2416,14 +2416,12 @@ mt7531_setup(struct dsa_switch *ds)
val = mt7530_read(priv, MT7531_TOP_SIG_SR);
priv->p5_sgmii = !!(val & PAD_DUAL_SGMII_EN);

- /* all MACs must be forced link-down before sw reset */
+ /* Force link-down on all MACs before internal reset */
for (i = 0; i < MT7530_NUM_PORTS; i++)
mt7530_write(priv, MT7530_PMCR_P(i), MT7531_FORCE_LNK);

/* Reset the switch through internal reset */
- mt7530_write(priv, MT7530_SYS_CTRL,
- SYS_CTRL_PHY_RST | SYS_CTRL_SW_RST |
- SYS_CTRL_REG_RST);
+ mt7530_write(priv, MT7530_SYS_CTRL, SYS_CTRL_SW_RST | SYS_CTRL_REG_RST);

if (!priv->p5_sgmii) {
mt7531_pll_setup(priv);
--
2.39.2